251
|
Talal N, Nakabayashi T, Letterio JJ, Kong L, Geiser AG, Dang H. Cytokines may prove useful in the treatment of Sjögrens syndrome (SS) dry eye. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 438:953-8. [PMID: 9634993 DOI: 10.1007/978-1-4615-5359-5_135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
252
|
Attias MR, Kong L, Tortolero M, Maccarone BG, Nakabayashi T, Talal N, Dang H. CD4 mononuclear cell infiltrates and Fas/Fas ligand positive mammary gland cells in breast tissue from a patient with Sjögren's syndrome. J Rheumatol Suppl 1998; 25:1226-31. [PMID: 9632092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We describe a 49-year-old patient with lip biopsy proven Sjögren's syndrome (SS) and keratoconjunctivitis sicca, who had dental caries, xerostomia, recurrent upper respiratory tract infections, arthritis in her hands, elbows and knees, and recurrent parotid inflammation. She developed bilateral breast nodules in 1988. Right breast nodules were excised in 1993 and 1995, but reappeared in 1996, requiring 2 more excisions. Breast tissue samples showed remarkable intralobular and perilobular mononuclear cell infiltrates that were predominantly CD4+ T cells and expressed bcl-2. A few cells stained CD20+ and CD8+. SS breast glandular epithelial cells stained more intensely for Fas compared to normal cells. CD4+ T cells and Fas mediated cell death may be involved in the mammary gland lesions in SS.
Collapse
|
253
|
Sakata K, Sakata A, Kong L, Dang H, Talal N. Role of Fas/FasL interaction in physiology and pathology: the good and the bad. CLINICAL IMMUNOLOGY AND IMMUNOPATHOLOGY 1998; 87:1-7. [PMID: 9576004 DOI: 10.1006/clin.1997.4504] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
254
|
Zhou M, Sutliff RL, Paul RJ, Lorenz JN, Hoying JB, Haudenschild CC, Yin M, Coffin JD, Kong L, Kranias EG, Luo W, Boivin GP, Duffy JJ, Pawlowski SA, Doetschman T. Fibroblast growth factor 2 control of vascular tone. Nat Med 1998; 4:201-7. [PMID: 9461194 PMCID: PMC3850292 DOI: 10.1038/nm0298-201] [Citation(s) in RCA: 298] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vascular tone control is essential in blood pressure regulation, shock, ischemia-reperfusion, inflammation, vessel injury/repair, wound healing, temperature regulation, digestion, exercise physiology, and metabolism. Here we show that a well-known growth factor, FGF2, long thought to be involved in many developmental and homeostatic processes, including growth of the tissue layers of vessel walls, functions in vascular tone control. Fgf2 knockout mice are morphologically normal and display decreased vascular smooth muscle contractility, low blood pressure and thrombocytosis. Following intra-arterial mechanical injury, FGF2-deficient vessels undergo a normal hyperplastic response. These results force us to reconsider the function of FGF2 in vascular development and homeostasis in terms of vascular tone control.
Collapse
|
255
|
Abruzzo GK, Flattery AM, Gill CJ, Kong L, Smith JG, Pikounis VB, Balkovec JM, Bouffard AF, Dropinski JF, Rosen H, Kropp H, Bartizal K. Evaluation of the echinocandin antifungal MK-0991 (L-743,872): efficacies in mouse models of disseminated aspergillosis, candidiasis, and cryptococcosis. Antimicrob Agents Chemother 1997; 41:2333-8. [PMID: 9371329 PMCID: PMC164124 DOI: 10.1128/aac.41.11.2333] [Citation(s) in RCA: 184] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The in vivo activity of the Merck antifungal echinocandin drug candidate MK-0991 (L-743,872) was evaluated in mouse models of disseminated candidiasis, aspergillosis, and cryptococcosis. The echinocandins are potent inhibitors of 1,3-beta-D-glucan synthase. Two models of disseminated candidiasis were used. In a Candida albicans mouse survival model with both DBA/2N and CD-1 mice, estimates of the 50% effective doses (ED50s) of MK-0991 were 0.04 and 0.10 mg/kg of body weight/dose at 21 days after challenge, respectively. In a C. albicans target organ assay (TOA) with DBA/2N mice, MK-0991 at levels of > or =0.09 mg/kg/dose significantly reduced the numbers of C. albicans CFU/g of kidneys compared to the numbers in the kidneys of control mice from 1 to 28 days after challenge. Even when given as a single intraperitoneal dose either 30 min or 24 h after challenge, MK-0991 was effective and significantly reduced the numbers of C. albicans CFU/g of kidney compared to those in the controls. MK-0991 was >300-fold less active when it was administered orally than when it was administered parenterally. MK-0991 was efficacious in mouse TOAs against other C. albicans strains and Candida species including Candida tropicalis, Candida (Torulopsis) glabrata, Candida lusitaniae, Candida parapsilosis, and Candida krusei. MK-0991 was ineffective against disseminated Cryptococcus neoformans infections. In the model of disseminated aspergillosis in mice, MK-0991 at doses of > or =0.02 mg/kg/dose significantly prolonged the survival of DBA/2N mice, with estimates of the ED50 and ED90 of MK-0991 being 0.03 and 0.12 mg/kg/dose, respectively, at 28 days after challenge. MK-0991 is a potent, parenterally administered therapeutic agent against disseminated candidiasis and aspergillosis that warrants further investigation in human clinical trials.
Collapse
|
256
|
Bartizal K, Gill CJ, Abruzzo GK, Flattery AM, Kong L, Scott PM, Smith JG, Leighton CE, Bouffard A, Dropinski JF, Balkovec J. In vitro preclinical evaluation studies with the echinocandin antifungal MK-0991 (L-743,872). Antimicrob Agents Chemother 1997; 41:2326-32. [PMID: 9371328 PMCID: PMC164123 DOI: 10.1128/aac.41.11.2326] [Citation(s) in RCA: 261] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The echinocandin MK-0991, formerly L-743,872, is a water-soluble lipopeptide that has been demonstrated in preclinical studies to have potent activity against Candida spp., Aspergillus fumigatus, and Pneumocystis carinii. An extensive in vitro biological evaluation of MK-0991 was performed to better define the potential activities of this novel compound. Susceptibility testing with MK-0991 against approximately 200 clinical isolates of Candida, Cryptococcus neoformans, and Aspergillus isolates was conducted to determine MICs and minimum fungicidal concentrations MF(s). The MFC at which 90% of isolates are inhibited for 40 C. albicans clinical isolates was 0.5 microg/ml. Susceptibility testing with panels of antifungal agent-resistant species of Candida and C. neoformans isolates indicated that the MK-0991 MFCs for these isolates are comparable to those obtained for susceptible isolates. Growth kinetic studies of MK-0991 against Candida albicans and Candida tropicalis isolates showed that the compound exhibited fungicidal activity (i.e., a 99% reduction in viability) within 3 to 7 h at concentrations ranging from 0.06 to 1 microg/ml (0.25 to 4 times the MIC). Drug combination studies with MK-0991 plus amphotericin B found that this combination was not antagonistic against C. albicans, C. neoformans, or A. fumigatus in vitro. Studies with 0 to 50% pooled human or mouse serum established that fungal susceptibility to MK-0991 was not significantly influenced by the presence of human or mouse serum. Results from resistance induction studies suggested that the susceptibility of C. albicans was not altered by repeated exposure (40 passages) to MK-0991. Erythrocyte hemolysis studies with MK-0991 with washed and unwashed human or mouse erythrocytes indicated minimal hemolytic potential with this compound. These favorable results of preclinical studies support further studies with MK-0991 with humans.
Collapse
|
257
|
Wang B, Yin P, Kong L. [A cytogenic study on colorectal carcinoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 1997; 26:218-21. [PMID: 10072867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
OBJECTIVE To study the cytogenesis of colorectal carcinoma and to look for colorectal carcinoma related chromosomal fragility sites which could facilitate screening of high risk colorectal carcinoma patients. METHODS 20 cases of surgically resected colorectal carcinomas and 4 cell lines were analysed cytogenetically. RESULTS Most of the tumor cells were heteroploid, the chromosome number was predominately hypodiploid. Karyotypic analysis demonstrated an increase of chromosome 13, and loss of chromosome 17 and chromosome 1 appeared frequently. The most frequently found structural abnormalities in colorectal carcinoma were breakpoint 1q21 and 1p13. Highly non-random cancer chromosome breakpoints and fragile sites were compared with the oncogene locus and found that their locus or neighboring locus was 1q21. CONCLUSION The results suggest that breakpoint 1q21 may be related to tumorgenesis and may be useful in screening and preventing colorectal carcinoma.
Collapse
|
258
|
Kong L, Korthuis RJ. Melanoma cell adhesion to injured arterioles: mechanisms of stabilized tethering. Clin Exp Metastasis 1997; 15:426-31. [PMID: 9219731 DOI: 10.1023/a:1018406422727] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
An isolated perfused vessel model was used to examine the mechanisms underlying the adhesive interactions between circulating tumor cells and subendothelial matrix in denuded arterioles. Arterioles ranging from 70 to 100 microm in diameter were isolated from rat mesentery, transferred to an isolated vessel chamber, cannulated on both ends with glass micropipettes, and perfused with media containing 10(6) hamster melanoma (RPMI 1856) cells/ml. In a second group of arterioles, the endothelium was denuded by running 2 ml of air through the vessel lumen. Since the tumor cells did not adhere to the vessel wall when perfused at physiologically relevant shear rates, perfusate flow was stopped and the tumor cells were allowed to settle onto the vessel wall for 20 min. After counting the number of tumor cells that settled onto the arteriolar wall, perfusate flow was re-initiated and unattached cells were washed away. The number of cells remaining adherent were counted and the percentage of adherent cells (relative to the total number of cells that settled on to the vessel wall during the period of no-flow) were calculated and compared among different groups. We observed that tumor cells are much more adhesive to denuded arterioles than to intact arterioles. To determine the mechanisms responsible for the adhesive interactions that become established and stabilized during the period of flow reduction, denuded arterioles were treated with fibronectin antiserum or Arg-Gly-Asp (RGD) peptides. Both treatments significantly reduced tumor cell adhesion to denuded arterioles. In subsequent studies, melanoma cells were treated with a transglutaminase inhibitor, monodansylcadaverine (MDC), which reduced the ability of adherent tumor cells to withstand the anti-adhesive effects of a subsequent increase in perfusate flow rate after the period of no-flow. Our data suggest that tumor cells adhere to fibronectin in the subendothelial matrix in denuded arterioles by an RGD-dependent mechanism. Moreover, our observations are consistent with the concept that a transglutaminase-catalysed reaction acts to stabilize the adhesive interactions between subendothelial matrix components and melanoma cells during the period of flow stasis such that the cells are able to withstand subsequent substantial increases in wall shear rate and remain adherent.
Collapse
|
259
|
Fang P, Ding R, Kong L. [The changes of fibrinolysis in plasma and wounds in rats inflicted with deep partial thickness burns]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1997; 13:259-63. [PMID: 10452009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We observed the changes in wound histopathology and fibrinolysis of rats with deep partial thickness burns during 10 days after scalding in order to study the relations of early progressive damage of deep partial thickness burn wound and the healing of the wound to fibrinolysis. Using Masson's trichrome stain of collagen, we demonstrated that partial thickness burn wound progressively deteriorated within 72 hours postburn, and epidermal cells on wound edge proliferated, creeping between necrotic and residual collagen by 10th day postburn. The results of assays of fibrinolytic parameters in plasma and 24 hour exudate from wound showed that fibrinolysis activated at 2 hour postburn but had been suppressed by 24 hour postburn till last day (10 day postburn) of the observation. The analysis of dynamic changes and relations in fibrinolytic parameters revealed that the suppressive factors of fibrinolysis might be enhanced activities of PAI, alpha 2-antiplasmin and antithrombin II after injury. Results suggested that suppression of fibrinolysis might protect fibrin deposited in the wound from lysis and play an important role in early progressive deterioration of deep partial thickness burn and regulation of its healing.
Collapse
|
260
|
Yang L, Jia L, Zou H, Kong L, Zhang Y. Immobilized IDA-type Cu2+-chelating membrane affinity chromatography for purification of bovine liver catalase. Se Pu 1997; 15:292-5. [PMID: 15739458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
Cu2+-chelating membrane medium based on iminodiacetate-substituted modified short cotton cellulose was examined to purify bovine liver catalase (BLC) by affinity chromatography. The buffer pH notably affect BLC binding to the Cu2+-chelating membrane adsorbent. The results showed that under the chromatographic conditions chosen, 67.7% recovery of BLC attained with an overall 4.7-fold increase in specific activity in a single step. After purification of BLC, the chelating membrane adsorbent can easily be regenerated by imidazole or EDTA buffer. Different results were obtained by the two regeneration methods: the later is more effective than the former in reviving the purification characters of the chelating membrane adsorbent.
Collapse
|
261
|
Nakabayashi T, Letterio JJ, Geiser AG, Kong L, Ogawa N, Zhao W, Koike T, Fernandes G, Dang H, Talal N. Up-regulation of cytokine mRNA, adhesion molecule proteins, and MHC class II proteins in salivary glands of TGF-beta1 knockout mice: MHC class II is a factor in the pathogenesis of TGF-beta1 knockout mice. THE JOURNAL OF IMMUNOLOGY 1997. [DOI: 10.4049/jimmunol.158.11.5527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Mice homozygous for a disrupted TGF-beta1 allele develop multiple lymphoproliferative disorders similar to those seen in the pseudolymphoma of Sjögren's syndrome. At 2 wk of age, these TGF-beta1 mutant mice begin to develop wasting syndrome and die at around 4 to 5 wk of age. We studied salivary glands from symptomatic mutant mice >14 days of age. Reverse transcriptase-PCR analysis showed up-regulation of proinflammatory cytokine genes such as IL-1alpha, IL-1beta, IL-2, IL-4, IL-6, IL-10, and IFN-gamma in these mutant mice. Enhanced expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1), and MHC class II as well as CD4-positive T lymphocyte infiltration was detected by immunostaining. To elucidate the role of MHC class II, salivary glands from TGF-beta1/MHC class II double knockout mice were used to investigate the expression of adhesion molecules and MHC class II. In spite of the existence of basal intercellular adhesion molecule-1 expression on vessels, there was neither MHC class II expression, enhanced vascular cell adhesion molecule-1 expression, nor lymphocytic infiltration in the salivary glands. These results suggest that MHC class II plays a significant role in the pathogenesis of TGF-beta1 mutant mice. Although the mechanism that initiates multiple inflammatory diseases in these mice remains unclear, the context reported here would provide insight into the immunopathology of Sjögren's syndrome.
Collapse
|
262
|
Nakabayashi T, Letterio JJ, Geiser AG, Kong L, Ogawa N, Zhao W, Koike T, Fernandes G, Dang H, Talal N. Up-regulation of cytokine mRNA, adhesion molecule proteins, and MHC class II proteins in salivary glands of TGF-beta1 knockout mice: MHC class II is a factor in the pathogenesis of TGF-beta1 knockout mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1997; 158:5527-35. [PMID: 9164977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Mice homozygous for a disrupted TGF-beta1 allele develop multiple lymphoproliferative disorders similar to those seen in the pseudolymphoma of Sjögren's syndrome. At 2 wk of age, these TGF-beta1 mutant mice begin to develop wasting syndrome and die at around 4 to 5 wk of age. We studied salivary glands from symptomatic mutant mice >14 days of age. Reverse transcriptase-PCR analysis showed up-regulation of proinflammatory cytokine genes such as IL-1alpha, IL-1beta, IL-2, IL-4, IL-6, IL-10, and IFN-gamma in these mutant mice. Enhanced expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule (VCAM-1), and MHC class II as well as CD4-positive T lymphocyte infiltration was detected by immunostaining. To elucidate the role of MHC class II, salivary glands from TGF-beta1/MHC class II double knockout mice were used to investigate the expression of adhesion molecules and MHC class II. In spite of the existence of basal intercellular adhesion molecule-1 expression on vessels, there was neither MHC class II expression, enhanced vascular cell adhesion molecule-1 expression, nor lymphocytic infiltration in the salivary glands. These results suggest that MHC class II plays a significant role in the pathogenesis of TGF-beta1 mutant mice. Although the mechanism that initiates multiple inflammatory diseases in these mice remains unclear, the context reported here would provide insight into the immunopathology of Sjögren's syndrome.
Collapse
|
263
|
Kong L, Yang S, Kong Z. [Treatment of congenital glaucoma with trabeculotomy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 1997; 33:169-72. [PMID: 10437027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To investigate the method of localization of Schlemm's canal during trabeculotomy to evaluate the successful rate of trabeculotomy. METHOD The author treated 38 cases (46 eyes) of congenital glaucoma with trabeculotomy. Harms trabeculotomy knife was introduced into the Schlemm's canal through the cutting end of an external collecting channel. The follow-up period was over 6 months in 37 eyes. RESULTS The intraocular pressure, C/D ratio were significantly improved after surgery compared to the preoperative ones (P < 0.05). But no significant differences were found in the corneal diameter, the depth of the anterior chamber, the length of ocular axis before and after surgery (P > 0.05). The intraocular pressure of 27 eyes (73.0%) was less than or equal to 2.8 kPa (1 kPa = 7.5 mmHg), showing good control of glaucoma. CONCLUSION During trabeculotomy, the trabeculotomy knife introduced in to the Schlemm's canal through an external collecting channel is a better and accurate method of localization of Schlemm's canal. The method is relatively simple, reliable and has certain value in clinical application.
Collapse
|
264
|
Smith JG, Kong L, Abruzzo GK, Gill CJ, Flattery AM, Scott PM, Silver L, Kropp H, Bartizal K. Evaluation of experimental therapeutics in a new mouse model of Helicobacter felis utilizing 16S rRNA polymerase chain reaction for detection. Scand J Gastroenterol 1997; 32:297-302. [PMID: 9140149 DOI: 10.3109/00365529709007675] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND A new mouse model of Helicobacter felis infection, which mimics the human infection observed with H. pylori, has recently been developed utilizing polymerase chain reaction (PCR) based on the 16S rRNA gene sequence for detection of infection. METHODS We tested several therapeutic regimens in this model, including some currently utilized in the clinic and some shown ineffective in the clinic. RESULTS The therapeutic results obtained by PCR with this model are consistent with results observed in the published human H. pylori clinical trials and also with results obtained in another H. felis mouse model utilizing culture and histology. CONCLUSIONS These results support further use of this new model in screening for new therapeutic regimens for the management of Helicobacter disease.
Collapse
|
265
|
Kong L, Ogawa N, Nakabayashi T, Liu GT, D'Souza E, McGuff HS, Guerrero D, Talal N, Dang H. Fas and Fas ligand expression in the salivary glands of patients with primary Sjögren's syndrome. ARTHRITIS AND RHEUMATISM 1997; 40:87-97. [PMID: 9008604 DOI: 10.1002/art.1780400113] [Citation(s) in RCA: 181] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To assess the role of Fas-mediated apoptosis in the salivary glands of patients with primary Sjögren's syndrome (SS). METHODS Expression of Fas, Fas ligand (FasL), and bcl-2 in salivary gland biopsy material was detected in situ by immunohistochemical staining and reverse transcriptase-polymerase chain reaction. DNA fragmentation in apoptotic cells was assessed by the enzymatic incorporation of labeled nucleotides (digoxigenin-dUTP). RESULTS The acinar epithelial cells in SS were Fas+ and FasL+, and these cells died by apoptosis. The majority of infiltrating lymphocytes in SS were Fas+ and bcl-2+, while few lymphocytes expressed FasL. In situ detection of apoptosis showed minimal cell death of lymphocytes, particularly in dense periductal foci. Lymphocytic cell death was significantly lower (P < 0.0001) in these foci compared with that in the interstitium. CONCLUSION Infiltrating lymphocytes in the focal lesions of the salivary glands of patients with SS are blocked in their ability to commit to apoptosis, even though they may express Fas. The presence of bcl-2 in these cells may explain their inability to undergo apoptosis. The acinar epithelial cells, in contrast, may undergo Fas-mediated apoptosis. These results suggest that the Fas death pathway may be an important mechanism leading to the glandular destruction found in SS.
Collapse
|
266
|
Zhuang Q, Gan J, Kong L, Wang H, Zhang Y. [Design and application of vacuum manifold for solid phase extraction]. Se Pu 1997; 15:49-50. [PMID: 15739434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
Solid phase extraction (SPE) is now a common method for sample pretreatment. SPE vacuum manifold is a key instrument when SPE is used for sample pretreatment. It was developed by National Chromatographic R. & A. Center. Being connected with a vacuum pump, it can deal with 12 samples simultaneously. The manifold has a unique rotatable cover and can be conveniently rotated when switching between any two steps of SPE. An application of this SPE vacuum manifold in measuring bile acids in human serum was given.
Collapse
|
267
|
Ogawa N, Dang H, Kong L, Anaya JM, Liu GT, Talal N. Lymphocyte apoptosis and apoptosis-associated gene expression in Sjögren's syndrome. ARTHRITIS AND RHEUMATISM 1996; 39:1875-85. [PMID: 8912510 DOI: 10.1002/art.1780391114] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To study the mechanism and regulation of apoptosis in peripheral blood T and B lymphocytes from patients with Sjögren's syndrome (SS). METHODS The mode of in vitro lymphocyte death in the peripheral blood of patients with SS was determined by fluorescence microscopic analysis, terminal deoxynucleotidyl transferase assay, and DNA fragmentation analysis. Apoptotic cell death of T and B cells was determined at 48 hours of culture by fluorescence-activated cell sorter analysis of propidium iodidestained cells. Messenger RNA (mRNA) expression of bcl-2, bcl-x, bax, and c-myc in T and B cells was determined by enzyme-linked immunosorbent assay-polymerase chain reaction (ELISA-PCR). Expression of bcl-xL and bcl-xS was determined by Southern blot analysis of PCR products. Gene expression was calculated as the ratio of each gene message to the message of the GAPDH gene. Bcl-2 protein levels in SS T cells were determined by ELISA. RESULTS SS T cells showed increased in vitro apoptosis compared with normal T cells (mean +/- SD 12.3 +/- 4.5% versus 7.3 +/- 2.0%; P < 0.01). Freshly isolated SS T cells showed increased expression of bcl-2 mRNA compared with normal controls (mean +/- SD 1.50 +/- 0.65 versus 0.88 +/- 0.23; P < 0.05). There was no significant difference in levels of bax or c-myc mRNA in T cells and B cells between SS patients and normal controls. When SS T lymphocytes were cultured in vitro for 72 hours, Bcl-2 protein levels decreased with time. CONCLUSION SS T cells showed accelerated apoptosis in vitro. Freshly isolated SS T cells had increased expression of bcl-2. An increase in death-promoter signals and decrease in death-suppressor signals in vitro may have been responsible, in part, for the apoptosis in SS T lymphocytes.
Collapse
|
268
|
Letterio JJ, Geiser AG, Kulkarni AB, Dang H, Kong L, Nakabayashi T, Mackall CL, Gress RE, Roberts AB. Autoimmunity associated with TGF-beta1-deficiency in mice is dependent on MHC class II antigen expression. J Clin Invest 1996; 98:2109-19. [PMID: 8903331 PMCID: PMC507656 DOI: 10.1172/jci119017] [Citation(s) in RCA: 168] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The progressive inflammatory process found in transforming growth factor beta1 (TGF-beta1)-deficient mice is associated with several manifestations of autoimmunity, including circulating antibodies to nuclear antigens, immune complex deposition, and increased expression of both class I and class II major histocompatibility complex (MHC) antigens. The contribution of MHC class II antigens to the genesis of this phenotype has been determined by crossing the TGF-beta1-null [TGF-beta1(-/-)] genotype into the MHC class II-deficient [MHC-II(-/-)] background. Mice homozygous for both the TGF-beta1 null allele and the class II null allele [TGF-beta1(-/-);MHC-II(-/-)] are without evidence of inflammatory infiltrates, circulating autoantibodies, or glomerular immune complex deposits. Instead, these animals exhibit extensive extramedullary hematopoiesis with progressive splenomegaly and adenopathy, surviving only slightly longer than TGF-beta1(-/-);MHC-II(+/+) mice. The role of CD4+ T cells, which are also absent in MHC class II-deficient mice, is directly demonstrated through the administration of anti-CD4 monoclonal antibodies in class II-positive, TGF-beta1(-/-) mice. The observed reduction in inflammation and improved survival emphasize the significance of CD4+ cells in the pathogenesis of the autoimmune process and suggest that the additional absence of class II antigens in TGF-beta1(-/-);MHC-II(-/-) mice may contribute to their extreme myeloid metaplasia. Thus, MHC class II antigens are essential for the expression of autoimmunity in TGF-beta1-deficient mice, and normally may cooperate with TGF-beta1 to regulate hematopoiesis.
Collapse
|
269
|
Wu H, Kong L, Wu M, Xi P. [Effects of different processed products of radix Angelica sinensis on clearing out oxygen free radicals and anti-lipid peroxidation]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1996; 21:599-601, 639. [PMID: 9772627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Different processed products of Radix Angelica Sinensis could clear out superoxide radical (O2.-) generated through hypoxanthinexanthine oxidase system and hydroxyl radical (.OH) generated through Fenton action, and inhibit lipid peroxidation of supernatant hepati homogenate in mice induced by free radical generation system. There exist significant differences among the different processed products.
Collapse
|
270
|
Kong L, Dunn GD, Keefer LK, Korthuis RJ. Nitric oxide reduces tumor cell adhesion to isolated rat postcapillary venules. Clin Exp Metastasis 1996; 14:335-43. [PMID: 8878407 DOI: 10.1007/bf00123392] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Adhesion of circulating tumor cells to microvascular endothelium plays an important role in tumor metastasis to distant organs. The purpose of this study was to determine whether nitric oxide (NO) would attenuate tumor cell adhesion (TCA) to naive or lipopolysaccharide (LPS)-treated postcapillary venules. A melanoma cell line, RPMI 1846, was shown to be much more adhesive to postcapillary venules isolated from rat mesentery than to corresponding precapillary arterioles. Although venules exposed to LPS for 4 h demonstrated an increased adhesivity for the melanoma cells, TCA to LPS-treated arterioles was not altered. Isolated venules exposed to DETA/NO (1 mM), an NO donor, for 30 min prior to tumor cell perfusion prevented the increment in adhesion induced by LPS and attenuated TCA to naive postcapillary venules. While L-arginine (100 microM), an NO precursor, failed to decrease TCA to naive postcapillary venules, this treatment abolished LPS-stimulated TCA to postcapillary venules. The effect of L-arginine was reversed by administration of N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM), an NO synthase (NOS) inhibitor. These observations indicate that both exogenous and endogenous NO modulate TCA to postcapillary venules. To assess the role of NO-induced activation of cGMP in the reduction in TCA produced by DETA/NO, two additional series of experiments were conducted. In the first series, LY-83583 (10 microM), a guanylyl cyclase inhibitor, was shown to completely reverse the effect of DETA/NO on TCA to both naive and LPS-activated postcapillary venules. On the other hand, administration of 8-bromoguanosine 3',5'-cyclic monophosphate (8-B-cGMP) (1 mM), a cell permeant cGMP analog, mimicked the effect of DETA/NO and reduced TCA to LPS-stimulated postcapillary venules. These data suggest that (a) tumor cells are more likely to adhere to postcapillary venules than to corresponding precapillary arterioles, (b) LPS enhances TCA to postcapillary venules, (c) both exogenously applied (DETA/NO) and endogenously generated (L-arginine) NO attenuate the enhanced adhesion induced by LPS, but only DETA/NO reduced TCA to naive postcapillary venules, and (d) the NO-induced reduction in TCA to LPS-activated postcapillary venules occurs by a cGMP-dependent mechanism.
Collapse
|
271
|
Ye D, Kong L. [Selection of technology for processing steamed Garcinia hunburyi with high pressure]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1996; 21:472-3, 510. [PMID: 9642407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The technology for processing steamed Garcinia hunburyi with high pressure was synthetically selected by using orthogonal experiment design, based on the indexes of anti-inflammatory, bacteriocidal, anti-tumour effects and gambagic acid content. The result shows that the best way is to steam for 0.5 h at 126 degrees C.
Collapse
|
272
|
Huang Q, Kong L, Wang L. Applications of frontier molecular orbital energies in QSAR studies. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1996; 56:758-765. [PMID: 8661859 DOI: 10.1007/s001289900111] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
273
|
Woo KR, Shu WP, Kong L, Liu BC. Tumor necrosis factor mediates apoptosis via Ca++/Mg++ dependent endonuclease with protein kinase C as a possible mechanism for cytokine resistance in human renal carcinoma cells. J Urol 1996; 155:1779-83. [PMID: 8627883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE Because renal cell cancers have been found to be resistant to numerous chemotherapeutic agents, other agents including tumor necrosis factor are now being considered for clinical use. In this study, we used 2 renal cancer cell lines. SK-RC-42 and SK-RC-49, and determined the cytotoxic effects of tumor necrosis factor (TNF) and the possible mechanism of TNF resistance. MATERIALS AND METHODS Cytotoxic assays, comparative reverse transcriptase-polymerase chain reaction (RT-PCR) and nuclease digestion analyses were used. RESULTS Cytotoxic assays with SK-RC-42 demonstrated that TNF at 50 ng./ml. for 24 hours resulted in 19% cytotoxicity of the cells. Similar assay with SK-RC-49 only demonstrated less than 4% cytotoxicity. Based on these results, we defined our TNF-sensitive cells as SK-RC-42 and SK-RC-49 as our TNF-resistant cells. To determine whether protein kinase C (PKC), which is involved in the signal transduction pathway of a cell, could regulate endogenous basal TNF mRNA levels, comparative PCR analyses for TNF expression were used. The PCR results demonstrated that the TNF-resistant cell, SK-RC-49, had a higher basal expression of TNF mRNA than the TNF-sensitive cell SK-RC-42. With PMA, a PKC activator, for various time points, both cell lines demonstrated an induction of endogenous TNF mRNA. To further confirm our findings that PKC may regulate endogenous TNF expression, a PKC inhibitor, staurosporine, was used. When the cells were treated with staurosporine prior to PMA stimulation, no increase in TNF mRNA expression was seen. To determine whether PKC is involved in providing resistance against TNF, we incubated the SK-RC-42 and SK-RC-49 cells with staurosporine at 100 nM. and TNF at 50 ng./ml. for 24 hours. After factoring out the cytotoxicity of staurosporine, the TNF-mediated cytotoxicity increased to 39.3% and 28.7% for the SK-RC-42 and SK-RC-49 cells, respectively. Furthermore, by using a nuclease digestion assay, we demonstrated that TNF activated a Ca++/Mg++ dependent endonuclease responsible for programmed cell death or apoptosis. CONCLUSIONS Our data suggest that protein kinase C may play a role in protecting renal cancer cells from undergoing cytokine-mediated apoptosis.
Collapse
|
274
|
Mecenas CA, Giussani DA, Owiny JR, Jenkins SL, Wu WX, Honnebier BO, Lockwood CJ, Kong L, Guller S, Nathanielsz PW. Production of premature delivery in pregnant rhesus monkeys by androstenedione infusion. Nat Med 1996; 2:443-8. [PMID: 8597955 DOI: 10.1038/nm0496-443] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The endocrine mechanism involved in term and preterm delivery in primates, including pregnant women, are poorly understood. In the term monkey, fetal plasma androgen concentration rises to two hundred times the maternal concentration which remains unchanged. Placental conversion of androgen to estrogen results in increased maternal plasma estrogen concentration at term in both pregnant nonhuman primates and women. In the present study, continuous infusion of androstenedione to 0.8 gestation monkeys resulted in the premature occurrence of labor-type myometrial activity and increases in maternal plasma estrogen, oxytocin and amnion fibronectin concentrations similar to those measured at normal-term labor. Androstenedione induction of these normal-term biochemical and endocrine changes accompanied by fetal membrane rupture, cervical dilatation and live delivery provides a rich opportunity to study the molecular and physiological mechanisms of both term and preterm labor in primates.
Collapse
|
275
|
Kong L, Ye D, Wang S, Xu Y, Bian J. [Acute toxicity and anti-inflammatory effect of processed products of gamboge]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1996; 21:214-6, 255. [PMID: 9208550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The acute toxicity and anti-inflammatory effect of processed and raw Gamboge were compared. The results showed that the acute toxicity of processed Gamboge was less than that of the raw one, while both had significant anti-inflammatory effect alike. Among the differently processed products, those boiled with lotus leaf juice and steamed by high pressure were better.
Collapse
|